This is a very intriguing topic, and I was surprised how quickly I was able to assemble a list. Sorry in advance for the novella.
My great-aunt used to doll me up and take me to her church when I was very small, and I loved how the Italian and French ladies dressed: fitted black lace dresses, heeled shoes, compact handbags, red lipstick, and the most delicious perfumes. Every woman looked like current-day Monica Bellucci in Dolce and Gabbana. To this day, I love vintage Gianni Versace, Dolce and Gabbana, Dior, and YSL.
My Italian grandfather's every day style (when he wasn't sweating it out as a carpenter) was to "dress sharp": immaculate grooming, casual slacks, polo shirt, leather belt and shoes, Aqua Velva, and his hair coiffed high (he had a mane worthy of Michael Landon).
My grandma was English, and born around the same time as the Queen. Elizabeth was her lifelong style icon - something I never really knew until I watched The Crown. My grandmother wasn't formal or fancy, but she had a beauty routine she followed every morning and night, her entire life, and she was always beautifully-groomed.
Film influences: Film Noir heroines, Vivienne Leigh, Marlene Dietrich, all the Hitchcock Blondes, Audrey Hepburn, Marilyn Monroe. Vera-Ellen in White Christmas. Fellini films.
1977 Nutcracker film (Kirkland/Baryshnikov): fitted pants, slightly flowy tops, fitted little jackets, tall, flat boots.
Junior high & high school was "Sloane Ranger", adventure- and safari-style via Indiana Jones and the Romancing The Stone, and elevated looks from The Love Boat, Fantasy Island, Designing Women, 227, and Dynasty (Joan Collins)
College: Paula Abdul! Tania Coleridge in George Michel's "Father Figure". I wanted everything they wore.
The 1990s... eh. I blank out here, because GenX and Grunge were the antithesis of everything I loved.
2000s, I moved Okinawa, and it sparked my love for tropical, Hawaiian, and Asian style. I discovered Dita von Teese, and she immediately became my style spirit animal.
Other significant influences: Valmont, Mad Men, Mrs. Maisel, Star Trek, The Crown.
During the pandemic, I've copied a lot of Kate Middleton's casual style: striped shirt, dark jeans, espadrilles and wedges.